Web roll controlling device for printing machines



A. J. HORTON 1,968,453

WEB ROLL CONTROLLING DEVICE FOR PRINTING MACHINES July 31, 193 1;

Original Filed.April 27, 1929 INVENTOR Patented July 31, 1934 WEB ROLL CONTROLLING DEVICE FOR PRINTING MACHINES Albert J. Horton, White m... n. 1, mmto B. Hoe da 00., Inc.,' New York, N. Y., a corporation of New York; receiver Irving Trust Company,

Original application April 27, 1929, Serial No.

358,481, now Patent No. 1,881,589, dated October 11, 1932. Divided and this application September 5, 1931, Serial No. 561,379

10 Claims. ((31. 242-75) The present invention relates to tension devices for controlling the unwinding 01 web rolls used with printing machines and is a division of application Serial No. 358,481 filed April 2'7, 1929, on which Patent No. 1,881,589 was granted on October 11, 1932.

- It is an object of the invention to provide a device that will so control a roll from which a web is being fed to a machine that prints, or otherwise operates upon it, as to automatically maintain a predetermined tension on the web, that will apply a brake to overcome the momentum oi the roll and prevent it from rimning ahead when the machine is deceleratedquickly, that will act when the machine is started, to instantly remove the brake pressure previously applied to the roll to stop it, and thus avoid imposing excessive strain on the web during the starting period, and that will include means to so control the action oi the mechanism that a 1 cannot'be applied relatively great brake pressure too rapidly.

' It is also an object of the invention to pro-' vide a tension device having a guide'roller that may be adjusted to compensate-tor any differ-- ence in length of opposite edges of the web, due to the roll being larger on one end than on the other.

It is also an object of the invention to provide a tension device for controlling web rolls of generally improved construction, whereby the device will be simple, durable and inexpensive in construction, as .well as convenient, practical, serviceable and eflicient in its use.

With the foregoing and other objects in view which will, appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it

being understood that various changes in the precise embodiment. of the invention herein"dis-.

. closed may be made within the scope of what the rise and fall oi the floating roller.

is claimed without departing from the spirit of the invention.

Web roll tension devices-have been used-in the past'in which a floating roller suchas is herein shown was used to automatically operate a brake which in turn controlled the rotation oi the web roll, the object being to maintain a substantially constant tension on the unwinding web, and a dash pot has been used to prevent rapid oscillation of the floating roller, as shown in Morse Patent 1,103,152 dated July 14, 1914;

In the Morse device the" dashpot restrains both A mechanism in the same class is disclosed in Jones Patent 1,395,830 dated November 1, 1921, in which the dash pot operates to retard the rise of the floating roller but allows it to descend without restraint. a

When a printing machine having the tension mechanism herein shown is running, a. tightening of the web reduces the brake pressure and a slackening oi the web increases it. When the machine is decelerated rapidly there is a tendency for the web roll to run ahead, but the slack thus formed allows the floating roller to descend and increase the brake pressure thereby checking the rotation of the roll.

. After a rapid deceleration the brake will remain applied to the roll with a heavy pressure but when the press is restarted the brake pressure will be instantly removed and thus allow the roll to rotate freely and avoid excessive strain on the web.

In the tension devices of this class that do not usea dash pot or its equivalent, under some conditions, particularly when running at certain slow speeds andwith a small web roll, having but little inertia, the freely moving floating roll, will sometimes execute what has been termed a hunting motion"; 1. e., when the machine is started the floating roller will rise, relieving the ,brake, and the roll ,will run ahead due to the weightoi the floating roller bearing on the web. The. slack thus formed allows the roller to descend quickly and apply the brake with force suiiicient to stop the roll. The continued pull of the web running to the machine then raises the floating roller and the cycle is repeated indefinitely with increasingly violent oscillation of the floating roller and it ultimately breaks the web in many instances.

The use of a dash pot connected to the support for the floating roller retards its motion and prevents the. hunting action. Howeyer, as hereto. tore used, it also prevents instantaneous action of floatingroller to relieve thebrake pressure when the machine is started, and consequently unless the brake. is slackened manually, excessive strain is'imposed on the web until the dash pot allows the floating roller to'rise. The mechanism disclosed herein, avoids this'difllculty.

In manycases the web-rolls are not evenly wound, being elliptical in section instead of circular. Due .to their inertia-the rolls tend to rotate at a constant speed, and when: feeding a web from a poorly wound roll it is necessary provide means to compensate dor the irregularity in the speed oi. the web as it unwinds. Rollers car- ..ried on springsupported bearingsand around which the webs are carried have been satisfactorily used for this purpose, but when web rolls of varying size are used, it is necessary to provide a separate roller of the correct length for each width of web, for if a narrow web is run adjacent to the end of a roller adapted to carry a full width web, the pull of the web at the-instant it is feeding from a low spot on the roll, will cause but one of the spring bearings to recede and in consequence one edge of the web is subjected to a strain which frequently breaks it.

A floating roller that has the required amount of free action will follow the irregularities of the running web, and when supported as herein shown is adapted to operate with either wide or narrow webs, and is provided with means whereby the supports carrying the bearings for the roll may be adjusted to compensate for variations in the length of opposite edges of the web and thereby maintain a constant and even tension throughout the width of the web running to the machine. A

In the drawing, Figure 1 shows the invention as applied to-a printing machine and as viewed from the side of the machine;

Figure 2 is a view partly in section and partly broken away showing the mechanism depicted in Figure 1 as viewed in the direction of arrow 2 of that figure;

Figure 3 is a view partly in section and partly broken away showing the arrangement depicted in Figures 1 and 2, the view being taken in the plane of the dotted line 3-3 of Figure 2 and viewed in the direction of the arrow;

Figure 4 is a fragmentary view partly in section showing the eccentric by means of which the brake is operated.

Referring to the drawing, 11 and 11' indicate frame members of a printing machine, and 12 a bracket secured thereto which is made with a well known form of open bearing for the spindle 13 on which a web roll 14 may be secured. A V- brake sheave 15 of the usual form is secured to the spindle 13 and is engaged by brake shoes 16, which are secured to arms 1'7 and 18. These arms are pivoted respectively by shafts 19 and 21 to the yoke 22, secured to the bracket 12.

The handwheel 23 has a right and left hand threaded shaft 24 which engages the correspond ingly screw threaded sleeves 25 and 26. The sleeve 25 is pivoted on the arm 18, and thesleeve 26 engages a stud on the arm 17. This is a well known form of hand tension device for controlling the roll as the web is drawn from it by the machine. The handwheel 28, which is also old in the art, is secured to a threaded shaft and serves to move the brake mechanism, and with it, the spindle 13, for adjusting the position of the web roll axially The shaft 21 is free to rotate in the yoke 22, and has an eccentric portion 29, which rotates in the hub of the arm 18. Thus, by rotating the shaft 21, the pressure of the brake shoes on the sheave 15 can be varied.

As shown in Figure 1, the web 31 is led from the roll 14, to and around a roller 32, having journals which rotate in bearings formed in brackets 33, secured to the side frames 11 and 11'. The web is then led to and around the floating roller 37, which is rotatably supported in the arms 38 and 38' that are carried by the shaft 39, which is journaled in bearings in brackets 41 and 41, secured to the frames 11 and 11. From this point, the web is led to printing cylinders-or other mechanism by which it is to be operated upon.

I The arm 38 is secured to the shaft 39, but means are provided whereby the arm 38 is adjustably connectedto the shaft. An arm 42 is secured to the shaft 39 and carries a screw 43, which passes through a clearance hole in the arm. The screw is provided with a thrust collar 44 and is screw threaded into a projecting lug on the arm 38. Thus, the arm 38 may be turned on the shaft by turning the screw 43., It will be understood that this mechanism provides means for raising or lowering the arm 38 with respect to the arm 38', to throw the roller out of parallelism with the roller 32 and the shaft 39, thus compensating for any difference in the length of opposite edges of the web due to the roll being larger on one end than on the other.

A dash pot 45 is pivotally supported on a bracket 46 secured to the frame 11 and a swivel connection 47 is rotatably held on one end of an arm 48 that is secured to the shaft 39. A collar 49, having a sleeve 51 is secured to the piston rod and provides an abutment for a relatively light spring 52, the other end of which bears against the swivel connection 47. Another collar 53 is screw threaded on the end of the piston rod and may be locked in place by a set screw. By turning the collar 53, the gap between the sleeve 51 and the'connection 47 may be adjusted to vary the free upward movement of the floating roller.

The dash pot may contain oil or any suitable fluid and is provided with a check valve, not shown, which allows the fluid to readily pass from the top of the piston to the under side, but which obstructs its passage in the reverse direction.

This construction is well known in the art and is more fully described in the patent hereinbefore referred to.

It will be seen that the floating roller may descend unrestricted by the dash pot, and that by compressing the spring 52, it may also rise freely for a limited distance which is governed by the space between the upper end of the sleeve 51 and the swivel connection 4'7, but any further upward motion is restricted by the dash pot.

A head formed on one end of the rod 54 is pivotally connected .to one end of the arm 48, and the other end of the rod slides in the swivel connection 55 which is supported so as to turn in the bracket 46.

A handwheel 5'7 is screw threaded on the rod 54 and presses against the spring 58, the other end of which bears against the swivel connection 55. The spring thus tends to resist the floating roller and its tension may be adjusted by turning the handwheel. An adjusting collar 59 is screw threaded on the lower end of the rod 54 and serves to limit the upward motion of the floating roller.

An arm 61 is secured to the shaft 39 and is pivotally connected to a rod 62, the other end of which is pivotally connected to an arm 63 secured to the shaft 21. It will thus be understood that a rise or fall of the roller 37 will result in turning the shaft 21 and reducing or increasing ter-clockwise and increasing the brake pressure applied to the brake.

It has been found that the mechanism herein disclosed can be so adjusted that the floatin roller will freely follow the irregularities in the web being drawn from the roll, and that the dash pot when properly adjusted, will permit the floating roller to rise with suflicient rapidity to prevent the roll from over-running when a press is decelerated or stopped quickly.

When the press is started, the brake is gradually tightened by means of the handwheel 23. This causes the floating roller to descend and the handwheel is so adjusted that'the roller assumes the position shown in the drawing. It is then unnecessary to change the setting while the web from the roll is being run off.

It will be seen that a mechanism has been provided that will act to restrain the rotation of a web roll when the web being fed therefrom slackens, that will reduce the restraint when the web tightens, that will prevent a too rapid application of the restraining action, will permit the restraint to be quickly removed when the machine is started, will follow irregularities in the run of the web coming from the roll and maintain a substantially constant tension on the web to the machine, and having a roller that may be adjusted to compensate for irregularities in the roll to thereby maintain an even pull on. the web.

What I claim is:

1. In a web roll controlling device, a floating roller moving transversely to its axis in response to variations in the slack of the unwinding web, a braking mechanism connected thereto, which acts to restrain the rotation of the. roll when the web slackens and to reduce the restraint when the web tightens, and a retarding device arranged to permit free movement of the floating roller when the web tightens and to restrict such movement when the web slackens; said floating roller being supported on arms secured to a shaft, one of said arms being adjustable to permit aligning the roller with respect to the web.

2. In a web feeding device, a roller bearing against the web, arms adapted to rotatably support-the roller, a rotatably supported shaft to which one of the arms is secured, and means for turning another of the arms with respect to the shaft and without disconnecting it therefrom, to position the axis of the roller out of or into a' plane common to the axes of the roller and the shaft.

3. In a web tension device, a roller bearing against the web, arms adapted to rotatably, support the roller, a rotatably supported shaft to which one of the arms is secured, means to press the roller against the web, and means for tuming one of the arms with respect to the shaft while it is connected thereto, to position the axis of the roller out of or into a plane common to the axes of the roller and the shaft.

4. In combination; a roller around which a web is led, a rotatably supported shaft, a pair of arms shaft, a pair of arms on the shaft adapted to rotatably support the first roller, a third arm secured to the shaft adjacent one arm of the said pair, and engaging means whereby the arm adjacent the third arm may be adjusted in relation thereto to move the axis of the roller out of or into parallelism with the secondroller; I c

6. In a device of the character described, a roller, a plurality of means for rotatably supporting said roller from a member in normal parallelism thereto, and other means connected to said member and at least one of said plurality of I means for inclining said roller relatively to said member.

'7. In a device of the character described, a roller, a support for the roller, and a plurality of members for connecting the said roller to the support, one of said members being movable relatively to the said support, others of said members being fixed to said support, and one of said other members having means to adjust the movable member for moving the roller slightly out of V parallelism with said support.

8. In a web feeding device, a roller in running engagement with the web, bearings for supporting the roller at each end, a rotatable shaft, means secured to the shaft for supporting one of the bearings, other means secured to the shaft for supporting the othercbearing, and means for independently moving it relatively to the shaft, whereby the roller may be moved slightly out of parallelism with respect to-other rollers in the machine to equalize the tension throughoutthe width of a web that is slack at one edge.

9. In a web feeding device, a roller around which the web is led, a shaft, arms on the shaft adapted-to rotatably support the roller, one of said arms being loose on the shaft, a member secured to the shaft, and means for moving the loose arm relatively to the member and securing it thereto, whereby the roller may be positioned slightly out of parallelism with respect to other rollers in the machine ,to equalize tension throughout the width of a web that is slack at one edge.

10. In a web feeding device, a roller in running engagement with the web, bearings for the roller, means for yieldingly supporting the bearings to permit their simultaneous motion only in the same direction and to the same extent to relieve stress on the web, and adjusting mechanism for moving one of the bearings relatively to the other bearing and securing it in relative position, to equalize the tension throughout the width of a web that is slack at one edge.

AIBER'I J. HORTON. 

